FFXIV's Systems Ain't That Deep, but They Could Have Been.

[kayll]

Cross-class abilities were dropped because they were a bad system, there's nothing more to that one, really.

Giving up on something because you aren't immediately good at it means you will never get better.
If they implement a system and its bad, then iterate on it until it is good.
If they just delete it instead of trying to improve it, then they must not have much of a vision for their game and are instead just throwing everything at the wall and seeing what sticks.

Imagine if instead of just outright deleting crossclass functionality, they built on it through all the years the games been out and what that system could have developed into?
FF14 would have had a system in it that set it apart from other MMOs.